ryridesmotox

Like the title says... Picked up a MP112 for ridiculously cheap, waiting on delivery right now, CAN'T WAIT. Going to put a new intake manifold and jackshaft on it to get proper belt offset. Originally the MP112 was on a C5 (and its still on the C5 manifold). My research has led me to believe that the C5 112 is a 1:1 rear pulley setup with a 3.0 front pulley. Is that true? I guess I assumed that all of the MP112s had the .83 rear ratio, but that was on the CTS-V models. So my plans are to do a 2.8 front and run the 1:1 rears shoot for like 10psi. Its a stock LS6 with long tubes. I'll get a cam to put in as well, I have LS9 springs in the heads also. Is that too much boost you think? I'd like to stay relatively safe. Not sitting for huge power goals here or I would have gone a different route. I couldn't pass up the deal.

My current plans are DW300, boost reference fuel pressure regulator (fuel lab, fast, or something along those lines), use stock fuel line as the return, -8 as supply to the rails, LS9 injectors. I'll be going meziere hx pump and frozen boost hx.

Any recommendations would be helpeful.

Jimbo1367

So how cheap is that?

NitrOmm

iTrader: (1)

You are correct re: 1:1.
Did you get the heat exchanger & pump as well ? You will need that to keep the IATs in check.
In addition, I would highly recommend the eight rib pulley system & heavy duty tensioner. You WILL have belt slip. My system was an OD 8" crank & 3.1 head unit pulley w/ an ECS HD tensioner. I was spinning at about 16,774 rpm making 9.5lbs through heads & cam & good flowing motor. You will be spinning about the same ... Probably will make the suggested 10 lbs. however, you will never see it without an eight rib setup.
For my two cents, save the aggravation and go with a larger head pulley ... 3 - 3.1 and settle for 7 lbs. plenty of fun on the street. You still will need the HD tensioner no matter what you do ( whether it's 6 or 8 rib). Many people will suggest differently, stating they have made Xxx without. Truth is, you are always slipping & don't know it. I learned the hard way.

If you do chose an eight rib system, PM me as I have an assortment of pulleys for the system as well as the ECS heavy duty tensioner ( which you will need either way). By no means do not take this as an advertisement to buy my left overs.
I am trying to save you aggregation as I have been through the war with the belt slip issues. Go less boost & save the money.

ryridesmotox

Thanks dude, PM sent about the pulleys and such.

As far as hr heat exchanger, I'll likely be getting the Ines out of the donor car. If not, I'll be going with an aftermarket setup, most likely a dual pass cobra with a Bosch or meziere pump.

I'm sworn to secrecy, sorry.

mkvamso

iTrader: (2)

Heat exchanger from a lightning can be picked up pretty cheap and they're a little easier to fit in a bumper

My 122 with an 8 inch crank pulley and 2.8 upper made around 11 lbs of boost
It was over spun quite a bit, iats would get high pretty quick with long highway pulls or hot lapping it at the track and start pulling timing

Belt slip will drive you crazy, I'd recommend a larger upper pulley if you stay with a 6 rib
They make loads of low end power and are really fun for a street car, and the noise they make is probably the best part...lol

1BADCTS

iTrader: (17)

If you are sending it in to Magnuson anyway, can't they instal quick change rear hubs on the case so you can play with pulley sizes to suit your combo? I thought I'd seen them do that for someone before.

ryridesmotox

I'll look into the quick change hubs. I'm pretty set for now on going with a 2.8 with 1:1 rears, I honestly don't know how often I'd swap hubs. And its not like I'll be getting rid of it any time soon.

I've honestly been thinking, if they can do this with the MP112, why can't I just run this for a while and grab a heartbeat later on. I got a buddy who is a machinist who can make me a manifold or an adaptor if need be. I mean... How hard can it be??? Lol

I'll check out the lighting intercoolers also. I might have a shot at getting the hx from the donor so I'm still in a holding pattern on that.